: It is generally considered legal to use a BIOS file only if you dump it from your own physical console . Downloading this file from "BIOS repositories" or ROM sites is technically copyright infringement.
If you are looking at a raw BIOS dump, the file you have is essentially a binary copy of rom0 . scph90001biosv18usa230rom0 top
One of the most notable features of the v18 BIOS is actually a missing feature—or rather, a hidden one. The original "fat" PS2s (SCPH-10000 through 50000) featured an expansion bay for a hard drive (HDD). The OS supported it natively. : It is generally considered legal to use